The present invention relates to remote convenience systems, and is particularly directed to systems in which an ability of a receiver/controller unit to receive a transmitted signal from a transmitter unit, located not more than a certain distance away from the receiver/controller unit, is generally isotropic.
Remote convenience systems are known in the art. Such remote convenience systems permit remote control of certain functions. One type of a remote convenience system is for remotely controlling vehicle functions. Other example types of remote convenience systems include garage door opener systems and entry light activation systems.
Focusing now on the remote convenience vehicle systems, examples of remotely controlled functions include locking and unlocking of one or more vehicle doors. Remote convenience vehicle systems that permit remote locking and unlocking functions are commonly referred to as remote keyless entry systems. Such remote convenience vehicle systems may provide for control of other vehicle functions. For example, a remote vehicle locator function may be provided. The vehicle locator function causes the vehicle arm to emit a horn chirp and/or the headlights of the vehicle to flash xe2x80x9cONxe2x80x9d. This allows a person to quickly locate their car within a crowded parking lot.
Known remote convenience vehicle systems include a receiver/controller unit mounted in an associated vehicle and at least one portable hand-held transmitter unit located remote from the receiver/controller unit. The receiver/controller unit is operatively connected to one or more vehicle systems (e.g., a door lock actuator system) that perform the functions that are remotely requested.
Each transmitter unit is provided with one or more manually actuatable switches. Each switch is associated with a remote control vehicle function to be performed. The transmitter unit includes circuitry that responds to the actuation of each switch to transmit a message in the form of a digital signal. When the receiver/controller unit receives such a digital signal, a controller portion of the receiver/controller unit outputs a signal to the proper vehicle system.
The reception of the transmitted signal by the receiver/controller unit is dependent upon the strength of the transmitted signal that reaches the receiver/controller unit and the ability of an antenna at the receiver/controller unit to pick-up the signal. The receiving antenna""s pick-up ability is influenced by directivity. Thus, remote control may be accomplished from a relatively long distance when the transmitter unit is located along a first direction from the receiving antenna, and remote control may be only accomplished from a relatively short distance when the transmitter unit is located along a second, different direction.
In accordance with one aspect, the present invention provides a remote convenience system for remotely controlling a convenience function. The system includes portable transmitter means for remote function requests. The transmitter means includes means for transmitting a signal that conveys a remote function request. Receiver/controller means of the system receives the transmitted system and causes performance of the remotely requested function. The receiver/controller means includes a plurality of antenna means, each for picking-up the transmitted signal and outputting an electrical signal that conveys the remote function request. Each of the plurality of antenna means is configured to have an ability to pick-up the transmitted signal that is dependent upon direction from the receiver/controller means to the transmitter means. The ability of each of the plurality of antenna means is different from the ability of the other of the plurality of antenna means. The receiver/controller means includes means for determining which one of the plurality of antenna means has a better ability to pick-up the transmitted signal. The receiver/controller means includes means for utilizing the electrical signal from the one antenna means to determine the remotely requested function.
In accordance with another aspect, the present invention provides a receiver/controller apparatus for a remote convenience system. The apparatus is responsive to a remote convenience function request conveyed via an electromagnetic signal transmitted from a portable transmitter for controlling performance of an associated function. The apparatus includes a plurality of antenna means, each having a reception pattern oriented in a different direction. Each antenna means for picking-up the electromagnetic signal and for outputting a respective, electrical antenna-output signal conveying the function request and having a strength related to the position of the transmitter with respect to the associated reception pattern orientation direction. Receive circuitry means processes one of the antenna-output signals and outputs an electrical signal conveying a function request in response to the processing of the one antenna-output signal. Signal selection means determines which antenna-output signal has a greater strength and causes the receiver circuitry means to process the antenna-output signal having the greater strength.
In accordance with yet another aspect, the present invention provides a receiver/controller apparatus that includes first antenna means, having a reception pattern oriented in a first direction. The first antenna means for picking-up the electromagnetic signal, and for outputting a first electrical antenna-output signal conveying the function request and having a strength related to the position of the transmitter with respect to the first direction. Second antenna means of the receiver/controller apparatus has a reception pattern oriented in a second direction that is different from the first direction. The second antenna means for picking-up the electromagnetic signal and for outputting a second, electrical antenna-output signal conveying the function request and having a strength related to the position of the transmitter with respect to the second direction. Receive circuitry of the apparatus processes one of the antenna-output signals and outputs an electrical signal conveying the function request in response to the processing of the one antenna-output signal. Signal selection means of the apparatus determines which antenna-output signal has a greater strength and causes the received circuitry means to process the antenna-output signal having the greater strength.
In accordance with still another aspect, the present invention provides a method for remotely controlling a convenience function. A signal that conveys a remote function request is transmitted. Each antenna, of a plurality of receiving antennae, is sequentially enabled during a portion of the transmitted signal. A value indicative of the reception ability of each antenna is derived. A determination is made as to which antenna is associated with better reception. Only the antenna associated with the determined better reception is enabled during a portion of the transmitted signal that conveys the remote function request. The remotely requested function is determined utilizing a signal that is output from the antenna associated with the determined better reception. The remotely requested function is performed.